Speaking on radio show LBC, the Foreign Secretary stalled as he was questioned on whether he would want to take over from Theresa May.
The staunch Brexiteer accused LBC political editor Theo Usherwood of being “ridiculous” and “absurd” as he repeatedly gave unclear answers.
Usherwood challenged Mr Johnson to “rule out being Conservative prime minister” after Mrs May.
Discussing the upcoming General Election and future Brexit talks, the Tory politican said: "The only choice at this election is between Theresa May and Jeremy Corbyn and I want to see Theresa May doing that deal and getting the right future for our country."
Mr Johnson took several attempts before he said: “I am ruling out any other serious possibility at this election except Theresa May.”
Boris Johnson failed a handful of times to answer whether he'd challenge for the Tory leadership
I am ruling out there being any other serious possibility at this election other than Theresa May
Pushed on whether he would put his hat in the ring if Mrs May failed to win a Tory majority at the General Election on June 8, Mr Johnson said: “Don’t be ridiculous.”
He was asked twice more to rule it out before giving a clear answer.
“Of course I’m ruling it out,” he said.
“What we want at this election is a strong administration led by Theresa. And that’s very much what I hope the British people will deliver.”
Meanwhile, the Conservatives have lashed out at Jeremy Corbyn after the Labour leader called out Mrs May for refusing to attend Wednesday's leaders debate.
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Politicians react to Theresa May's snap general election Wed, April 19, 2017
UK Prime Minister Theresa May has announced her intention to hold an early general election on June 8
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Theresa May has called for a snap general election
The veteran politician confirmed he would take part during a rally this afternoon, in which he criticised the Tories for what he called "a stage-managed arms-length campaign".
He said: “I will be taking part in tonight’s debate because I believe we must give people the chance to hear and engage with the leaders of the main parties before they vote.
Lib Dem leader Tim Farron, UKIP's Paul Nuttall, SNP deputy leader Angus Robertson, Green co-leader Caroline Lucas and Plaid Cymru leader Leanne Wood will also participate in the televised showdown.
But a Tory party spokesman confirmed there will be “no changes to the Prime Minister’s plans” regarding tonight’s debate.
Amber Rudd will still appear in place of Theresa May on the BBC show.